FIG. 1 depicts a vertical cross-section of a typical food waste disposer. The disposer may be mounted in a well-known manner in the drain opening of a sink using mounting members of the type disclosed in U.S. Pat. No. 3,025,007, which is owned by the assignee of the present application.
The disposer includes an upper food conveying section 12, a lower motor section 14, and a central grinding section 16 disposed between the food conveying section and the motor section. The food conveying section 12 includes an injection-molded plastic housing 18 that forms an inlet 20 at its upper end for receiving food waste. The food conveying section 12 conveys the food waste to the central grinding section 16. The motor section 14 includes an induction motor 22 imparting rotational movement to a motor shaft 24. The motor 22 is enclosed within a motor housing 26 having a die-cast metal upper end frame 28, a stamped metal lower end frame 30, and a stator band 32 extending between the upper and lower end frames 28 and 30.
The grinding section 16 includes a grinding mechanism having a circular plate 34, a pair of lugs 36, and a stationary shredder ring 38. The plate 34 is mounted to the motor shaft 24 of the motor section 14. The lugs 36 are fastened to the plate 34 but are free to rotate relative to the rotating plate 34. The grinding section 16 includes a die-cast metal housing 40 integrally formed with the die-cast upper end frame 28 of the motor housing 26. The combination of the housing 40 and upper end frame 28 may be referred to as an upper end bell. The housings 18, 40, and 26 of the respective food conveying section 12, grinding section 16, and motor section 14 are fastened together by a plurality of bolts 41. To prevent the food waste from leaking between the housings 18 and 40, a rubber O-ring 43 is inserted therebetween.
The housing 40 of the grinding section 16 encompasses the grinding mechanism. The shredder ring 38, which includes a plurality of spaced teeth 42, is fixedly attached to an inner surface of the housing 40. In the operation of the food waste disposer, the food waste delivered by the food conveying section 12 to the grinding section 16 is forced by the lugs 36 against the teeth 42 of the shredder ring 38. The sharp edges of the teeth 42 grind the food waste into particulate matter sufficiently small to pass from above the grinding plate 34 to below the grinding plate 34 via gaps between the teeth 42 outside the periphery of the plate 34. Due to gravity, the particulate matter that passes through the gaps between the teeth 42 drops onto the upper end frame 28 and, along with water injected into the disposer, is discharged through a discharge outlet 44 into a tailpipe 46. As best shown in FIG. 2, the tailpipe 46 is connected to the discharge outlet 44 by a non-conventional fitting consisting of a gasket 48, a flange 50, and a pair of screws 52.
Although the food waste disposer in FIG. 1 operates efficiently and effectively, manufacturers are continually striving to facilitate the manufacture and assembly of such disposers and reduce manufacturing costs without sacrificing the efficiency and effectiveness of the disposer's operation.